Field of the Invention
The present invention relates to a method of testing waterproof performance of a radiological imaging apparatus, and a radiological imaging apparatus. More particularly, the present invention relates to a method of testing waterproof performance of a radiological imaging apparatus that includes radiation detecting elements two-dimensionally arranged.
Description of the Related Art
There are various kinds of radiological imaging apparatuses that have been developed to generate charges at detecting elements in accordance with the dosage of emitted radiation such as X-rays, and read out the generated charges as image data. Radiological imaging apparatuses of this type are known as FPDs (Flat Panel Detectors), and have been conventionally designed as special-purpose apparatuses (also referred to as anchored apparatuses) integrally formed with supporting bases or the like. In recent years, radiological imaging apparatuses of a portable type (also called a cassette type or the like) that have detecting elements and the like housed in housings and can be carried around have been developed and already been put into practical use.
Like a CR (Computed Radiography) cassette conventionally used in radiological imaging, such a portable radiological imaging apparatus has features special-purpose radiological imaging apparatuses do not have. For example, such a portable radiological imaging apparatus can be mounted on a bucky apparatus (see FIG. 4, which will be described later) or be applied directly to the body of a patient, or a patient can be placed on the radiological imaging apparatus during an imaging operation.
However, when a radiological imaging apparatus is applied to the body of a patient, or a patient is placed on a radiological imaging apparatus as described above, urine or blood of the patient might adhere to the radiological imaging apparatus. If the urine or blood adhering to the radiological imaging apparatus penetrates into the housing of the apparatus, the sensor panel (denoted by SP in FIG. 2, which will be described later) having electronic components and the like placed therein might be short-circuited due to the urine or the like penetrating into the housing, or some components might be broken or deteriorate, for example.
Therefore, when the radiological imaging apparatus is subjected to routine maintenance or everyday inspections, for example, a check needs to be made to determine whether the radiological imaging apparatus maintains waterproof performance. As a method for such a check, JP 2009-121965 A discloses a waterproof performance testing method. According to JP 2009-121965 A, an air pressure sensor is included in the housing of an apparatus, and the apparatus is placed in a testing device. The air pressure in the apparatus is measured as the atmospheric pressure outside the apparatus is changed. A check is then made to determine whether the waterproof performance of the apparatus is normal based on whether the measured air pressure in the apparatus is equal to or lower than a predetermined amount of air pressure change.
JP 2010-151656 A also discloses a waterproof performance testing method. According to JP 2010-151656 A, the housing of an apparatus contains an air pressure sensor, a temperature sensor, and a temperature changing unit that changes the temperature in the housing. The change in the air pressure with respect to the temperature before and after the temperature in the housing is changed by the temperature changing unit is measured with the air pressure sensor. The result of the determination is compared with a theoretical value calculated in a case where the housing is completely sealed, and the waterproof performance of the apparatus is then determined.
However, in a case where the waterproof performance testing method disclosed in JP 2009-121965 A is applied in testing the waterproof performance of a radiological imaging apparatus, there is the need to not only prepare a testing device equipped with a chamber or the like that can change the inner air pressure, or but also take the testing device to a place where the radiological imaging apparatus exists or take the radiological imaging apparatus to a place where the testing device exists. Therefore, the waterproof performance of the radiological imaging apparatus is not readily tested.
In a case where the waterproof performance testing method disclosed in JP 2010-151656 A is applied in testing the waterproof performance of a radiological imaging apparatus, it is necessary to prepare not only an air pressure sensor but also a temperature sensor and a temperature changing unit that changes the temperature in the housing. Furthermore, after the temperature in the housing is changed by the temperature changing unit, a long period of time is required until the temperature stabilizes, and an even longer period of time is required to test the waterproof performance of the radiological imaging apparatus.